/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
export default class CRC32Hash {
    private static CRC32_POLY: number = -306674912;
    static crcTable: Int32Array = new Int32Array(256);

    constructor() {
    }

    static crcTableCrc() {
        for (let i: number = 0; i < 256; ++i) {
            let crc: number = i;

            for (let j: number = 0; j < 8; ++j) {
                if ((crc & 1) != 0) {
                    crc = crc >>> 1 ^ -306674912;
                } else {
                    crc >>>= 1;
                }
            }

            this.crcTable[i] = crc;
        }

    }
}

CRC32Hash.crcTableCrc()